We believe that no experimental study has yet tested Darwin's idea that, as well as generating trait elaboration, intersexual selection might sometimes drive sex-biased trait reduction. Here we present the results of two experiments exploring the negative relationship between tail length and reproductive success in male golden-headed cisticolas (Cisticola exilis). In the first experiment, artif...

Reproduction is an economically important complex composite trait in sheep. Genetic improvement of composite traits can occur by selection for individual components traits, some combination of individual component traits, or by direct selection for the composite trait. This review discusses the responses of selecting directly for litter weight weaned compared to selection responses for one of i...

The rainbow trout is a salmonid fish that occasionally exhibits broodstocks with biannual spawning behavior, a phenomenon known as a double annual reproductive cycle (DARC). Spawning time quantitative trait loci (SPT-QTLs) affect the time of the year that female rainbow trout spawn and may influence expression of the DARC trait. In this study, microsatellite markers linked and unlinked to SPT-Q...

Disposition has been shown to significantly affect feed intake and growth rates of beef cattle. However, little research has evaluated the effects of poor disposition, and methods to improve this trait, on reproductive function of beef females. Thus, two experiments were conducted to determine the effects of disposition and acclimation to human handling on reproductive function of mature cows a...

Heterosis is an important phenomenon in agriculture. However, heterosis often greatly varies among hybrids and among traits. To investigate heterosis across a large number of traits and numerous genotypes, we evaluated 12 life history traits on parents and hybrids derived from five Arabidopsis thaliana ecotypes (Col, Ler-0, Cvi, Ws, and C24) by using a complete diallel analysis containing 20 hy...

Sexual coevolution occurs when changes in the phenotype of one sex select for changes in the other sex. We can identify the "footprint" of this coevolution by mating males and females from different populations and testing for a male-female genotype interaction for a trait associated with male (or female) performance. Here we mated male Drosophila melanogaster from five different continents wit...

In this study phenotypic and genetic factors affecting the reproductive efficiency of Lori-Bakhtiari ewes were determined using 8202 reproductive records of 2478 ewes collected at Shooli research station in the southwestern part of Iran (Shahrekord) during 1989 to 2012. Reproductive efficiency over all consecutive lambing opportunities were calculated by adding the total reproductive efficiency...

Sexual selection and ecological differences are important drivers of speciation. Much research has focused on female choice, yet the role of male competition in ecological speciation has been understudied. Here, we test how mating habitats impact sexual selection and speciation through male competition. Using limnetic and benthic species of threespine stickleback fish, we find that different ma...

The study of ecosystem functioning - the role which organisms play in an ecosystem - is becoming increasingly important in marine ecological research. The functional structure of a community can be represented by a set of functional traits assigned to behavioural, reproductive and morphological characteristics. The collection of these traits from the literature is however a laborious and time-c...

Behavioral ecology and ecology have projects in common. Community ecology can provide behavioral ecology with the tools to ask realistic questions about the current action of natural selection. Evolutionary ecology has moved beyond asking ‘‘Why does trait x contribute to reproductive success?’’ and on to ‘‘What are the conditions under which trait x contributes to reproductive success?’’ We nee...